The Role of Leukotriene B4 in Cow Metritis.

Introduction: Metritis is a common postpartum disease in dairy cows. As a mast cell (MC) mediator, leukotriene B4 (LTB4) is the strongest phagocyte chemokine. It is important in inflammation for the recruitment of immune cells to resist infection. This study investigated the effect of LTB4 in metritis. Material and Methods: Twenty Holstein cows 3 to 6 years old and at 6 to 10 days postpartum were selected, ten of which with postpartum metritis were the experimental group, and the other ten of which as healthy cows were the control group. The levels of LTB4, substance P (SP) and vasoactive intestinal peptide (VIP) were measured by ELISA, the expression of LTB4 receptor 2 (BLT2), matrix metalloproteinase (MMP)-2 and MMP-9 mRNA was measured by qPCR, and collagens I and IV were detected by immunohistochemical staining. Results: Concentrations of SP and LTB4 were significantly higher, but those of VIP were significantly lower in the experimental group than those in the control group. The expression of BLT2, MMP-2 and MMP-9 mRNA was significantly higher in the experimental group than that in the control group. The expression of collagen Ⅰ and collagen Ⅳ was significantly lower in the experimental group than that in the control group. Conclusion: In metritis, SP promotes the activation of MC and the synthesis and release of LTB4. Leukotriene B4 chemotactic immune cells promote the high expression of collagenase, which accelerated the hydrolysis of collagen, while the inhibitory effect of VIP on MC was weakened. This may further aggravate the damage to uterine tissue.

Depression and the risk of breast cancer: a meta-analysis of cohort studies.

BACKGROUND: Whether depression causes increased risk of the development of breast cancer has long been debated. We conducted an updated meta-analysis of cohort studies to assess the association between depression and risk of breast cancer. MATERIALS AND METHODS: Relevant literature was searched from Medline, Embase, Web of Science (up to April 2014) as well as manual searches of reference lists of selected publications. Cohort studies on the association between depression and breast cancer were included. Data abstraction and quality assessment were conducted independently by two authors. Random-effect model was used to compute the pooled risk estimate. Visual inspection of a funnel plot, Begg rank correlation test and Egger linear regression test were used to evaluate the publication bias. RESULTS: We identified eleven cohort studies (182,241 participants, 2,353 cases) with a follow-up duration ranging from 5 to 38 years. The pooled adjusted RR was 1.13(95% CI: 0.94 to 1.36; I2=67.2%, p=0.001). The association between the risk of breast cancer and depression was consistent across subgroups. Visual inspection of funnel plot and Begg's and Egger's tests indicated no evidence of publication bias. Regarding limitations, a one-time assessment of depression with no measure of duration weakens the test of hypothesis. In addition, 8 different scales were used for the measurement of depression, potentially adding to the multiple conceptual problems concerned with the definition of depression. CONCLUSIONS: Available epidemiological evidence is insufficient to support a positive association between depression and breast cancer.

[Gas chromatographic determination of micro organic impurities in 3-chloro-2-hydroxypropyl trimethyl ammonium chloride].

A simple, rapid and reliable method for the determination of micro organic impurities, epichlorohydrin and 1,3-dichloropropanol, in 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTMA) by gas chromatography is reported. 2-Ethylhexanol was the internal standard. Epichlorohydrin and 1,3-dichloropropanol in CHPTMA were extracted by chloroform. The gas chromatographic separation was achieved on a stainless steel column packed with 10% PEG 20M/Chromosorb W/AW and with a flame ionization detector. The ranges of recovery were 97.5%-105.0% and 93.3%-98.8%, the RSDs were 11.5% and 13.1% and the mininum detectable concentrations were 5.0 micrograms/g and 10 micrograms/g for epichlorohydrin and 1,3-dichloropropanol respectively.